A technique has conventionally been disclosed for an active inductor that has a characteristic that corresponds to an inductor, by combining a passive element such as a resistor or a capacitor with an active element such as a transistor, and an amplifier circuit with such an active inductor that is provided as a load thereof.
A direct electric current electric voltage drop at a load of an amplifier circuit causes reduction of a dynamic range of such an amplifier circuit. Furthermore, a frequency characteristic of an amplifier circuit is influenced by a frequency characteristic of a load. Hence, an active inductor with a small electric voltage drop and a stable frequency characteristic is desired.